What can’t you find on Google? Vital statistics: “Here’s a cheap trick to play on an audience – especially one drawn from the business community. Ask them how many use Microsoft software. Virtually every hand in the room will go up. How many use Apple Macs? One or two – at most. How many use Linux? If the audience is drawn from corporate suits, no hands will show. Now comes the punchline: who uses Google? A forest of hands appears. ‘Ah,’ you say, ‘that’s very interesting, because it means you’re all Linux users.’ Stunned looks all round.

The computing engine that powers Google is the largest cluster of Linux servers in the history of the world. If you talk to computer-science folks, you find that they regard this – rather than the number of web pages indexed – as the most interesting thing about the company. Managing such a vast server-farm is a formidable task. For example, how do you implement security patches and operating-system upgrades (much more frequent in Linux than in proprietary systems from Microsoft or Sun) on thousands of servers without causing disruption to service? Google manages to achieve this with sophisticated techniques for rippling changes through the cluster, yet achieves 100 per cent uptime. This is serious stuff, and there are a lot of IT managers out there who would give their eye-teeth to be able to do it half as well.” —Guardian.UK